The Tao of It and Bit by Cristinel Stoica

Cristi,

I hope this link will work: Demystifying the Delayed Choice Experiments by B Gaasbeek (2010), arXiv:1007.3977v1 [quant-ph] 22 Jul 2010. I am curious.

Eckard

Cristi

My comment about is has happened was in the context of observation. In general, mu comment about happened is that something definitive occurred, existence does not do vagueness. So the point is thatobservation can have no effect on the physical circumstance, and if we cannot discern what actually happened then that is our failure, not some inherent characteristic of physical existence.

Paul

Christi,

The statement "The experiment confirmed the theoretical prediction." is incorrect.

The experiment confirmed that the interference pattern vanishes. But it failed to confirm that the cause for the vanishing is due to the cause that was predicted. It was not.

The situation is analogous to preventing two cars from interfering (colliding) with each other at an intersection. Delaying one car will prevent the collision, but so will completely eliminating one car.

In effect, the experiment simply eliminates one travel path, via a spatial filter. The delayed choice is irrelevant - if there is no path, there can never be any interference, regardless of any delayed choice.

The telescope I was referring to is not an astronomical one. It is part of the laboratory interferometer, and used to "choose" the slit.

Rob McEachern

Dear Cristi,

While I consider myself unbiased, I enjoy common sense arguments like your delayed initial condition, Rob's car accident comparison, and Paul's independence of reality from observation. Of course, as an EE, I am familiar with the impossibility to measure something without disturbing it, for instance because there is no voltmeter with infinite resistance. The disturbed reality is not the reality one intends to observe.

When I asked you whether your idea has already been supported, I meant ideal support by other experts. I guess that it may be understood as undermining Wheeler's intention to justify his absorber theory, travel backward in time, and it from bit. Perhaps, many honest experts will be cautious, and I doubt that there will again be almost 300 contributions to the contest this time, although in particular the many experts of computer science are now addressed.

Best regards,

Eckard

Eckard

"Of course, as an EE, I am familiar with the impossibility to measure something without disturbing it"

There are two aspects to that statement:

-the practical which you allude to, ie the degree to which measuring accurately and comprehensively captures what actually occurred

-the more fundamental point that measuring/observing/etc, cannot affect what occurred, because it has already occurred. And, whilst that is sufficient to dispense with this false notion that observation/consciousness/etc has a physical role, suffice it to say that the interaction involves a physically existent representation of what occurred anyway, and not the occurrence itself, which is usually light.

Paul

Cristi

"If by "happened" we understand..."

Well it is not possible to observe something which has not happened. And my concept of observe includes valid hypothesis, ie virtual sensing. That is, what demonstrably could have been observed had it been possible to do so.

The concept of time revolves around the rate at which alteration occurs. That is, there is no time (because there is no alteration) within a reality. Time relates to a feature of the difference between realities, ie speed of 'turnover'. Timing being the measuring system whereby we calibrate it by comparing different rates and identifying the difference. Events can only occur in a sequence. And presuming that something very bizarre does not happen to light in its travels, then we will receive a light based representation of the sequence in the right order. The frequency is more likely to be affected. Existence can only occur this way, which again points to the fact that whilst 'classical' is not understood properly, QM is based on a flawed premise. Nothing can occur 'out of sequence', it is impossible. Neither can something be in different spatial locations at the same time, or in different states at the same time. They must be different. The problem is with our inability to observe/discern what is actually happening at the existential level. Reality does not guess or choose anything. We are the problem, and people should stop adjusting reality to overcome it.

"But each one of them, including mine, had to start from a point which contradicts common sense"

And there is the alarm bell for the fact that the theory is wrong. What is, physically, a wavefunction, it is certainly more than one physically existent state.

Paul

Cristi

The answer to your specific question is I do not know. But the point is that something happens, ie it is knowable if we had the wherewithall to discern it. Put the other way around, nothing happens which is contrary to how existence occurs, ie there is no pre-existent future, neither does observation cause a particular existence from a range of options, etc, etc.

Paul

Cristi

There is no mystery, I am not a physicist, never claim to be one, and never make assertions about what is physically happening. I speak in the generic, and at a simple level, which is not philosophy. How what I am saying, generically, manifests physically, is an entirely different matter. But what I do not do is alter the rules whereby existence occurs and we detect it, in order to get a metaphysical theory to work.

Paul

Hi Eckhard,

thanks for the link, the paper is interesting for me too.

I read it and i think it is yet too technical for the average reader to understand. At least i didn't understand what is the "true" reason for the interference pattern to disappear in the case the screen is moved out of the experimental setup (Appendix A: Wheeler's thoughts).

Can anybody explain it to me in more intuitive words, with destructive and constructive interference instead of conditional probabilities and all that stuff. Means, that stuff is highly abstract but i want to know how one can put it in terms of physical processes (be it with or without time ordering).

Thanks in advance,

Stefan

Dear Christi,

your essay was an interesting read. I think your realization that ultimately, all we know of the world are relations is very deep, and is in a certain sense at the foundation of my own thinking, as well. However, I am less certain about the 'book containing every truth': this seems to me to run into trouble with the Kochen-Specker theorem (and related ones). In particular, if such a book existed, it would imply the existence of a global probability distribution such that its marginals give the outcomes for every possible set of observations; but this is known to be at variance with quantum mechanics. Put differently, while classically we can identify every object with a list of properties, of propositions true about this object, in quantum mechanics, no such list can exist. Any theory for which such a list exists necessarily obeys Bell's inequalities (and Kochen-Specker and Leggett-Garg inequalities, which are from this point of view just variations on a theme). (I think this connection was probably first worked out by Fine.)

Nevertheless, your big book seems to be very much a 'hot idea' in philosophy at the moment, after having been somewhat maligned after the 'noble failure' of Carnap's "Der Logische Aufbau der Welt"; three books have appeared in the past year dealing in various ways with the possibility of deriving all truths about the universe from some 'compact class' of basic truths: David Chalmers' "Constructing the World" (which is the only one I've read... well, I should say 'almost read'), Theodore Siders' "Writing the Book of the World", and John Heil's "The Universe as we Find It", so you're certainly at the bleeding edge in that respect! (Just in case you're interested.)

In any case, as a fellow PhD student in physics, I wanted to emphasize one point you made, though only somewhat implicitly, and only tangentially related to the main thrust of your essay: that of the necessity for courage in the scientific endeavour. Building on the Kuhnian model of scientific revolution, one might say that the ordinary, stick-to-the-mainstream method of science fails to produce the most important new ideas: it only clusters around local maxima, so to speak. For true innovation, one must sometimes leap beyond what seems reasonable, or even sensible within the current paradigm. Of course, many, if not most, such leaps will lead to nothing, which is why one needs courage to make them---a courage which John Wheeler certainly possessed, as you have shown in your essay.

Cristi

No, it means I have not got the knowledge to explain it, that does not make it a mystery. And no experimentation can differentiate one physically existent state, because of the degree of complexity and duration involved, along with the fact that we only receive a light based representation of it anyway, which makes it more impossible than it already was(!).

So even if I had more knowledge, I would not be inclined to junk what must be how physical existence occurs, for an alternative explanation which cannot possibly support existence, in order to accommodate what appears to be the result of experimentation, when experimentation cannot differentiate existence at the existential level.

Paul

Dear Cristi,

"it comes from experiment, not from a metaphysical theory." Wasn't Wheeler's original experiment just a Gedankenexperiment intending to support his theory?

I understand your intention to not get suspected as someone who questions Einstein's theories while you simultaneously maintain your desire to explain what are so far mysteries to you. Yes, George Ellis and many others were successful trying the same in the contests. However, in reality being a bit pregnant is impossible. I have to admit that I was mislead e.g. by Feist's experiment. The truth is sometimes unexpectedly simple.

Paul,

I am not interested in quarreling with you. We agree in many decisive points. However, I still tell you that in any (stationary) electric measurement the non-ideal impedance of the instrument disturbs the voltage or current to be measured. The instrument correctly measures a quantity that in reality belongs to the disturbed case. Knowing the error, we may exactly calculate the undisturbed reality. The latter possibility also holds for two-way non-Poincaré synchronization.

Eckard